Vật lý A level:AQA PHYA2 QP JAN12

Tài liệu ôn thi UEE, học bổng chính phủ Singapore, Nhật, Phần Lan, học bổng ASEAN, Vật lý A level: Câu hỏi và đáp án

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Candidate Signature

General Certificate of Education Advanced Subsidiary Examination January 2012

Time allowed

l 1 hour 15 minutes

Instructions

l Use black ink or black ball-point pen.

l Fill in the boxes at the top of this page.

l Answer all questions.

l You must answer the questions in the spaces provided Do not write

outside the box around each page or on a blank page.

l Do all rough work in this book Cross through any work you do not

want to be marked.

l Show all your working.

Information

l The marks for questions are shown in brackets.

l The maximum mark for this paper is 70.

l You are expected to use a calculator where appropriate.

l A Data and Formulae Booklet is provided as a loose insert.

l You will be marked on your ability to:

– use good English

– organise information clearly

For this paper you must have:

l a pencil and a ruler

l a calculator

l a Data and Formulae Booklet (enclosed).

Physics A PHYA2

Unit 2 Mechanics, Materials and Waves

Friday 20 January 2012 9.00 am to 10.15 am

Mark Question

Examiner’s Initials

TOTAL

1 2 3 4 5 6 7

Answer all questions in the spaces provided.

and ship’s engines work together to power the ship One of these sails is shown in

Figure 1 pulling at an angle of 40oto the horizontal

Figure 1

1 (a) The average tension in the cable is 170 kN

is 1.3 × 108J

(2 marks)

1 (b) With the sail and the engines operating, the ship is travelling at a steady speed

of 7.0 m s–1

1 (b) (i) Calculate the power developed by the sail

answer = W

(2 marks)

tension 40º

1 (b) (ii) Calculate the percentage of the ship’s power requirement that is provided by the wind

when the ship is travelling at this speed

answer = %

(2 marks)

1 (c) The angle of the cable to the horizontal is one of the factors that affects the horizontal

force exerted by the sail on the ship State two other factors that would affect this

force

Factor 1

Factor 2

(2 marks)

Turn over for the next question

8

2 An ‘E-bike’ is a bicycle that is assisted by an electric motor Figure 2 shows an E-bike

and rider with a total mass of 83 kg moving up an incline

Figure 2

2 (a) (i) The cyclist begins at rest at A and accelerates uniformly to a speed of 6.7 m s–1at B.

The distance between A and B is 50 m.

answer = s

(2 marks)

2 (a) (ii) Calculate the kinetic energy of the E-bike and rider when at B Give your answer to an

appropriate number of significant figures

answer = J

(2 marks)

A

B

2 (a) (iii) Calculate the gravitational potential energy gained by the E-bike and rider between A

and B.

answer = J

(2 marks)

2 (b) Between A and B, the work done by the electric motor is 3700 J, and the work done by

the cyclist pedalling is 5300 J

2 (b) (i) Calculate the wasted energy as the cyclist travels from A to B.

answer = J

(2 marks)

2 (b) (ii) State two causes of this wasted energy.

Cause 1

Cause 2

(2 marks)

Turn over for the next question

10

3 Figure 3 shows an aircraft designed to take off and land vertically and also to hover

without horizontal movement In order to achieve this, upward lift is produced by

directing the jet engine outlet downwards The engine also drives a vertical lift fan near

the front of the aircraft The weight of the aircraft is 180 kN The distance between the

lift fan and the centre of mass is 4.6 m and the distance between the jet engine outlet

and the centre of mass is 2.8 m

Figure 3

3 (a) (i) Calculate the moment caused by the weight of the aircraft about the point X.

answer = N m

(2 marks)

3 (a) (ii) By taking moments about X, calculate the lift fan thrust if the aircraft is to remain

horizontal when hovering

answer = N

(3 marks)

lift fan outlet

centre

of mass

jet engine outlet

X

weight

4.6 m

lift fan thrust

engine thrust 2.8 m

lift fan

3 (a) (iii) Calculate the engine thrust in Figure 3.

answer = N

(1 mark)

horizontally The aircraft accelerates horizontally to a maximum velocity The forward

thrust produced by the jet is 155 kN The weight of the aircraft is 180 kN

the aircraft

answer = m s–2

(2 marks)

3 (b) (ii) State and explain one characteristic of the aircraft that limits its maximum horizontal

velocity

(2 marks)

Question 3 continues on the next page

3 (b) (iii) On the axes below, sketch the velocity-time graph for the horizontal motion of the

aircraft as it accelerates from zero to its maximum horizontal velocity

(2 marks)

3 (c) State how a velocity-time graph could be used to find the maximum acceleration

(1 mark)

Turn to page 10 for the next question

0

horizontal

velocity

13

There are no questions printed on this page

DO NOT WRITE ON THIS PAGE ANSWER IN THE SPACES PROVIDED

4 Figure 4 shows a stress-strain graph for a copper wire.

Figure 4

(1 mark)

answer = Pa

(1 mark)

Label this point A.

(1 mark)

your answer

0.0

strain/10–3

fracture

0.4 0.8 1.2

1.6 1.8 2.0

stress/108Pa

0.2 0.6 1.0 1.4

4 (e) The area under the line in a stress-strain graph represents the work done per unit volume

to stretch the wire

of 3.0 × 10–3

answer = J m–3

(2 marks)

4 (e) (ii) Calculate the work done to stretch a 0.015 kg sample of this wire to a strain of

3.0 × 10–3

answer = J

(2 marks)

4 (f) A certain material has a Young modulus greater than copper and undergoes brittle

fracture at a stress of 176 MPa

material

(2 marks)

Turn over for the next question

12

5 (a) In an experiment, a narrow beam of white light from a filament lamp is directed at

normal incidence at a diffraction grating Complete the diagram in Figure 5 to show

the light beams transmitted by the grating, showing the zero-order beam and the

first-order beams

Figure 5

(3 marks)

information about the gases that make up the outer layers of the star

(2 marks)

mm to measure the wavelength of the laser light

narrow beam

filament

lamp

grating

5 (c) (ii) Describe the necessary procedure in order to obtain an accurate and reliable value for

the wavelength of the laser light

6 Figure 6 shows a glass prism Light is directed into the prism at an angle of 56o

The path of the ray of light is shown as is it enters the prism

Figure 6

answer =

(2 marks)

6 (a) (ii) Calculate the critical angle for the glass-air boundary.

answer = degrees

(2 marks)

6 (b) On Figure 6, continue the path of the ray of light until it emerges from the prism.

(2 marks)

6

56°

30°

60°

30°

ray of

light

7 Figure 7 shows a continuous progressive wave on a rope There is a knot in the rope.

Figure 7

7 (a) Define the amplitude of a wave

(2 marks) 7 (b) The wave travels to the right Describe how the vertical displacement of the knot varies over the next complete cycle.

(3 marks) 7 (c) A continuous wave of the same amplitude and frequency moves along the rope from the right and passes through the first wave The knot becomes motionless Explain how this could happen

direction of wave motion rope

There are no questions printed on this page

DO NOT WRITE ON THIS PAGE ANSWER IN THE SPACES PROVIDED